Edelbrock RPM Air-Gap Small Block Ford 351W Intake Manifold - Chrome Plasma FinishEdelbrock part #7581 CP RPM Air Gap 351W intake manifold is designed for street and high performance 351 427 c. i. d. 351W Ford V8 applications. The RPM Air Gap incorporates the same race winning design that's been used on our Victor Series competition intakes for decades. The Air Gap design features an open air space that separates the runners from the hot engine oil resulting in a cooler, denser charge for more power. Larger cross sectional area and